Pusher type automatic plating apparatus



Sept. 1, 1953 J. V. DAVIS PUSHER TYPE AUTOMATIC PLATING APPARATUS 7Sheets-Sheet 1 Filed June 18, 1947 INVENTOR.

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7 PUSHER TYPE AUTOMATIC PLATING APPARATUS Filed June 18, 1947 7Sheets-Sheet 7 INVENTOR.

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Patented Sept. 1, 1953 PUSHER TYPE AUTOMATIC PLATING APPARATUS John V'.Davis, Detroit, Mich, assignor to The Udylite Corporation, Detroit,Mich., a corporation of Delaware Application June 18, 1947, Serial No.755,365

16 Claims. 1

The present invention pertains to a. novel apparatus for conveying workthrough a succession of tanks or receptacles in an electroplatingoperation and also for lifting the work in order that it may betransferred over the partitions that separate the receptacles from oneanother.

The problem of lifting the work in order that it may be transferred overthe partitions has resulted in numerou complicated, expensive andawkward mechanisms. One of the objects of this invention is to provide acomparatively simple mechanism for this purpose. In this respect thework-carrying railconsists of spaced sections mounted fixedly over thetank and intervening sections carried by a vertically movable chassis. A

Oscillating pusher bars for propelling the work on the rail are carriedby the chassis. The operation of the apparatus is timed so that the workis on th movable sections when ready for transfer. The chassis then rses, carrying with, it the movable sections and the pusher bars, and thebars advance the work'when the chassis is in its upper position. Thechassis then descends to bring the movable section in line with thefixed sections, and the pusher bars are again actuated to advance thework in the receptacles.

A continuous plating apparatus often comprises two mutually adjacentrows of receptacles and a curved connecting rail section at one or bothends. The work pieces on the curved rail section converge toward thecenter of the curve and consequently have a tendency to crowd or engageone another with detrimental results. This difficulty can b avoided byincreasing the spacing of the work on the curved rail section, andanother object of the invention is to prdvide a simple apparatus forthis purpose.

A shaft is rotatably mounted in the center of the curved rail sectionand carries a pair of arms which in turn carry pushers operative on thissection. The arms are angularly spaced apart half the extent of thecurve, so that two movements of the shaft are necessary to pass the workover the entire curve. The shaft is oscillated by a link connected tothe means, for reciprocating the pusher bars, and the free end of thelink' has the same linear displacement as the pusher bars. Theaforementioned arms operating on the curved rail section haveapproximately the length of the link, or are slightly longer. As a,result, the linear displacement of the arcuately, moving pushers on thearms is greater than the pushers on the pusher bars, so that the workpieces are spaced farther apart on the curved rail section than on thestraight portions thereof.

The difference is sufficient to avoid the aforementioned crowding.

The invention is fully disclosed by way of example in the followingdescription and in the accompanying drawings in which:

Figure 1 is an elevation of the device with the chassis in raisedposition;

Figure 2 is a top plan view of the device;

Figure 3 is a section on the line 3--3 of Figure 2;

Figure 4 is a bottom plan view on the line t-4 of Figure 3;

Figure 5 is a detail side elevation on the line 5-5 of Figure 4;

Figure 6 is a section on the line 6-45 of Figure 2;

Figure 7 is a section on the line 1--T of Figure 1;

Figure 8 is a side elevation of the device with the chassis in the lowerposition;

Figure 9 is a detail top plan view on the line 9-9 of Figure 1;

Figure 10 is a section on the line l0l0 of Figur 9;

Figure 11 is a section on the line |I-ll of Figure 10;

Figure 12 is a.- section on the line l2l2 of Figure 8;

Figure 13 is a detail section in a plane parallel to that of Figure 5;

Figure 14 is a section on the line I l-I4 of Figure 13, and

Figure 15 is a diagram illustrating unequal spacing of pusher members atdifferent lengths of the, pusher bar.

Reference to these views will now b made by. use of like characterswhich are employed to designate corresponding parts throughout.

The machine is built upon a suitable base I' on which is erected anelongated tank structure 2 consisting preferably of metal plate. Thestructure is divided by a longitudinal partition 3 and again by a numberof suitably spaced partitions 4 forming two parallel rows ofcompartments 5. Upon the partition 3 is secured a longitudinal I- beam 6(Figure 7) to support a superstructure as willpresently be shown. At theends and at the center of the beam 6 are mounted vertical columns 3 andSi, as shown in Figure To the upper ends of the columnsv are securedangle irons it on which are mounted horizontal connecting box beams i I,thereby bracing the columns for the load to be carried by them. Thebeams I l terminate somewhat short of the end column 9' and have theirends joined by a bracket [2 for a purpose that will presently bedescribed. The memhers I l are extended somewhat beyond the column 9 bybeams l3 secured to the outer edges thereof,

and the latter are further extended horizontally in the same directionby channels |4 secured to their inner surfaces and also to the column 9.The bracket l2 serves for the pivotal attachment of the closed end of afluid cylinder l5 that extends approximately to the column 9. The pistonrod It extending through thi end of the cylinder carries a crosshead l1pivotally attached thereto by a horizontal pin I8. The ends of thelatter ride between spaced horizontal guide rails l9 fastened on themutually facing surfaces of the respective channels M. A bracket 2|] ismounted on the upper end of the column 9 and carries a sheave 2 I.Cables 22 and 23 are fastened to the ends of the crosshead ll. The cable22 passes over the sheave 2|, and the cable 231s passed over a pulley 24mounted at the opposite end of the beam structure I The cables 22 and 23suspend a vertically movable structure comprising an enclosing wall 25substantially as long as the series of tanks and about as wide. The wall25 carries a floor consisting of open plates 23 and is suitably bracedby cross bars 2?. Suitable roller frames 28 are mounted on the floor andcarry rollers 29 riding on the vertical columns to guide the structurein its up and down movement.

Transverse supporting bars 30 are secured across the beam 6 and haveplates 3| secured. across their ends for supporting fixed and spacedrail sections 32, with insulation 33 inserted between the parts 3| and32. The sections 32 are alined along both rows of compartments, andincluded in the fixed rail construction is a semicircular connectingpiece 34 at each end of the apparatus. The tank structure is open at oneend to constitut a loading and unloading station. One of thecompartments at this end may be open and constitute a drying station onthe outcoming side of the curved section. If the compartment at theincoming side of the curved section is closed, the work is lifted overits end Wall in the same manner that it is lifted over the severalpartitions, as will presently be described. Brackets 35 (Figures 3 and5) on th bottom of the chassis 25, 23 carry movable rail sections 36adapted to enter and fill the spaces between the fixed sections 32 toform a continuous work-carrying rail when the chassis is lowered.Current is supplied to the continuous rail in any manner well known inthe art, and work carriers 31 are suspended from the several railsections in any approved manner. A pair of pusher bars 38 (Figures 4 and5) of T-section are mounted in shoes 39 carried by the bottom of thechassis. The pusher bars 38 correspond respectively to the two alinedseries of rail sections and lie above the sections 32. Fixed pushers 40and pivoted pushers 4| (Figure 5) are carried by the bars 38 and areadapted to operate on the work carriers. The pushers 4| are constructedto pivot only on being retracted and are provided wherever a pusher musttravel across a work carrier in being retracted. A suitable stopincorporated in each such pusher and adapted to engage the pusher bar onthe pushing movement will hold the pusher from pivoting at this time.Both sets of pushers are adjustable lengthwise on their supporting bars33 by positioning their supporting pins 49 shown in Figure 5.

The pusher bars are actuated from a drive or pusher cylinder 42 mountedon the chassis 25, 25 adjacent to and longitudinally of one of the bars.At each end of the chassis is mounted a vertical shaft 43 concentricallywith the adjacent curved rail section and passing through the bottom ofthe chassis. Each shaft is held in suitable bearings 44 attached topartitions 45 carried by the chassis. The shaft 43 nearer the cylinder42 has a link 43 secured to and pivotally connected to the exposed endof the piston rod 41 by a suitable swivel 48. The partition 45 carryingthe bearings 44 is formed with an opening 43 to permit passage of thelink 43 and piston rod 4'! therethrough. In other respects the assemblyat both ends of the rail is alike, and only one assembly need bedescribed in detail.

Beneath the bottom of the chassis the shaft 43 carries a pair of fixedarms 58, 5| at a right 7 angle to each other. From the arm 55 a lug 52extends toward the cylinder 42 and is joined by a link 53 to an ear 54on the adjacent pusher bar, the link having its ends swiveled to theparts 52 and 54. The forward stroke of the piston rod 41 is such as toswing the link 46 and turn the shaft 43 through an angle of to thedotted line position shown in Figure 4. The arm 58 turns with the shaftand pulls the adjacent pusher bar 38 by means of the parts 52, 53. A lug55 extending from the arm 5| is joined by a link 55 to an ear 5'!extending from the other pusher bar 38, so that the aforementionedmotion of the shaft 43 slides the last named bar 38 simultaneously inthe direction opposite to that of the other bar 38. At the other end ofthe apparatus, the bar 38 nearer the cylinder 42 is connected to the arm50 by a link 53. The free ends of the arms 55, 5| carry pushers 59 thatpropel the work 90 on the end sections 34 on each 90 movement of theshaft 43 when the chassis is in the lower position. The closed end ofthe cylinder 42 is pivotally mounted to accommodate the arcuate movementof the swivel 48. r

The superstructure carries limit switches 69 and GI at opposite sides ofthe cross head ll and engageable thereby for a timed control of thelifting cylinder I5 and the drive cylinder 42 in a sequence presently tobe described. For the same purpose the partition 45 carries limitswitches 62 and 63 engageable by the arms 50 and 5| at the ends of theirrespective movements.

The timed cycle of operation is as follows: Let it be assumed that thechassis is in the lowered position and th pushers are behind therespective Work carriers. At this time the pushers are spaced about twoinches behind the carriers, having been retracted to this position toavoid clashing with the carriers on the previous downward movement ofthe chassis. The cylinder 42 then operates to advance the link 46 90 tothe position shown in Figure 4, thereby advancing all the carriers. Thelinear travel of the pushers may be, for example, 18" to impart a 16movement to the carriers on the straight parts of the continuous rail.on engagement of the limit switch 63 by the lug 55, the lifting cylinderl5 is energized to raise the chassis with its movable rail sections 36and the carriers. The crosshead l6 eventually contacts the switch 6| toarrest the operation of the lifting cylinder and again energize thedrive cylinder 42 to retract the pushers to positions behind thecarriers on the sections 33. At the end of the retracting movement, thearm 53 engages the switch 62 to advance the piston rod 41 and advancethe work on the lifted rail sections 36. The work pieces thereby crossthe respective partitions 4 so that each piece willf enter the nextcompartment on the subsequent descent of the chassis. This socalledtransfer movement is terminated by th engagement of the switch .63 .bylog 55., whereupon the chassis commencesto descend through theoperation-of the lifting cylinder. The descent is terminated .by theengagementof the crosshead H with the switch -60 whereupon the. drivecylinder 42 is op- :erated to retract the poshers to positions behindthe work carriers for the beginning of another cycle.

The construction around the shafts 43 is designed to avoid (crowding andcontacting of the Wonk pieces as they converge toward the shaftsrounding the turns 34. such crowding would occur the linear travel onthe turns WI-211211013 greater than on the straight portions of therails,

and the disclosed construction makes the "first displacement greaterthan the second although simultaneous therewith. lnalgiyen construction,the lengths of. the 4-6 and the arms 50, 5 are respectively Ill/ L2? and12".. .A 9.0 turn of. the shaft .43., from full to the dotted lineposition shown in Figure 4., will displace the free end of the link adistance of 16.3", which .is the maximum possible spacing betweensuccessive workpieces on thestztaig'ht parts =01 the rail. The

90 length of curved rail section traversed by the pushers 259 on thesame movement of the shaft 1371s 18.5"", providing a wider spacing .atthe work :pieceslon the curved sections than on the zst-raight portionsof the :rail.

Unequal travels of selected workpieces may be obtained by unequalspacing of the .pushers. For example, :a dipping travel .of 1" isdesired, this be accomplished Iby providing two successive pushers 3"apart over the dipping compartment, allowing for a2 rearward overlap, aspreviously indicated.

Likewise, variation of the spacing of the work pieces in variouspositions of the track may be accomplished by regulating the spacing ofthe pushers. This applies 'to the straight portions of the track as well:as at the curve. For example, as shown in Figure 1-5, the stroke of thepushers being uniform throughout the track at 18', a 14" spacing of thework pieces may he desired in certain baths and is obtained by spacingthe pushers 14" :apart the corresponding lengths of the track. Theoverlap or lost motion "in this case is 4" on each stroke. Similarly, ifanother bath favors a 17" spacing of the work pieces, the pushers arehere spaced 17" apart. In the rinsing compartments, aspacing of 12 maybe sulficien-t, and in such case the pushers are spaced 12" apart in thecorresponding lengths of track, leaving an overlap of 6 in an 18" pusherstroke.

It will be understood that the particular figures given here are merelyillustrative.

There is still another advantage in providing unequally spaced orlengthwise adjustable pushe-rs on a reciprocating pusher bar. Manyinstallations are made up of a number of complete and separate tankslaid end to end in abutting relation, rather than by dividing a longtank by partitions as here shown. The separate tanks, although madeaccording to specifications, are not accurately dimensioned. They mayvary from 4 inch to nearly 1 inch in overall length. Also, the end wallsmay not be perfectly perpendicular to the base. Either of these errorsintroduces an alteration in the calculated center distance betweentanks. Such errors are cumulative and may amount to a few inches for theentire installation. Another practice contributing to the same result isthe thickening of the walls of certain tanks, for example, by means of afive inch brick 6 wallvfor achromium where accuracy within as. smallfraction :of :an .inchis not maintained.

The nnpredioted variation in the center distence between tanks requiresa corresponding adjustment in the position of the pushers. the ease of aunidirectional chain as applicant's prior Patent .No. 2,479,322 ofAugust Mi, 1949,, the adjustment can be made only in terms of integrallengths of :a link. Moreover, since the charm travels over the entireseries of tanks any particular adjustment is not localized :to any :tankor smollgroup KM tanks. .As a result the adjustment :in the spacing ofthe pushers must be sufiicient to. compensate 'for :all the assemblyerrors throughout "the system and is therefore of greater mgnitude thanrequired only by the magnitude or the errors.

Arecipnocating. pusher :bar :on the other hand, is localized opemat-iveon only asmall number of tanks. The adjustment of the primers thereon isto the :conresponding tanks and :need not account liar the accumulatederrors in the system. net result is that an .acouratezlocal :adiustment:is obtainable and. there :is less. waste of tank length and workingspace thaninmeiking adjustments of the pushers in a unidirectional chainsystem as above described.

Although a specific embodiment of the invenhas been illustrated anddescribed,..it will he understood that various alterations .in thedetails of constructions may he made without departing from'the scope orthe haventton as indicated by the appended clams.

What I claim is:

.1. In a conveying apparatus, a series of receptacles, aimed series orspaced rail sections fixedly supported. over :said receptacles, amovably mounted over said receptacles, means for moving said chassis upand down over receptacles, a series of spaced sections carried by saidchassiscand adapted to lit in the spaces between the host named sectionsin the lower posttionof the chassis, slidably mounted pusher has carriedby said chassis, means for reciprocating :said bars, lengthwiseadjustable pushers carried by said bars close proximity to the movablerail sections and adapted to engage work on the several rail sections ineither position of the chassis, and means for sliding said bars in bothpositions of the chassis.

2. In a conveying apparatus, a series of receptacles, an alin'ed seriesof spaced rail sections fixedly supportedover said receptacles, achassis mova-bly mounted over said receptacles, means formov mg' saidchassis up and down over said receptacles, aseries of spaced railsection-s carried by said chassis and adapted to fit in the spacesbetween the first named sections in the lower position of the chassis,slid-ably mounted pusher bars carried by said chassis, pus'hers carriedby said bars in close proximity to the movable rail sections and adaptedto engage work on the several rail sections in either position of thechassis, and means for sliding said bars in both r positioned thechassis, certain of the said pushers being pivotally mounted to swingover obstructions While moving in the non-pushing direction.

3. In a conveying apparatus, a series of recepitacles, an a'lined seriesof spaced rail sections fixedly supported over .said receptacles, achassis movably mounted over said receptacles, means for moving saidchassis and down over said receptacles, a series of spaced rail sectionscarried by said chassis and adapted. to fit in the spaces between thefirst named sections in the lower position of the chassis, slidablymounted pusher bars carried by said chassis, unequally spaced pusherscarried by said bars in close proximity to the movable rail sections andadapted to engage work on the several rail sections in either positionof the chassis, and means for sliding said bars in both positions of thechassis.

4. The device as set forth in claim 3 further characterized by certainof said pushers being pivotally mounted to swing over obstructions whilemoving in the non-pushing direction.

5. In a conveying apparatus, two spaced receptacles, straight railsections over said receptacles, an arcuate section connecting saidstraight rail sections, pusher bars slidably mounted along said straightsections, pushers extending from said bars toward said straightsections, a shaft rotatably mounted in the center of curvature of saidcurved section, an arm fixed to said shaft, linkage connecting said armto one of said bars, means for oscillating said shaft, a pusher on saidarm and adapted to extend close to said arcuate section, and aconnection from said shaft to the other bar.

6. In a conveying apparatus, two spaced receptacles, straight railsections over said receptacles, an arcuate section connecting saidstraight rail sections, pusher bars slidably mounted along said straightsections, pushers extending from said bars toward said straightsections, a shaft rotatably mounted in the center of curvature of saidcurved section, a pair of arms fixed to said shaft and spaced apart halfthe angular extent of said arcuate section, linkage connecting said armsrespectively to said bars, means for oscillating said shaft, and pusherson said arms and adapted to extend close to said arcuate section.

7. In a conveying apparatus, two spaced receptacles, straight railsections over said receptacles, an arcuate section connecting saidstraight rail sections, pusher bars slidably mounted along said straightsections, pushers extending from said bars toward said straightsections, a shaft rotatably mounted in the center of curvature of saidcurved section, an arm fixed to said shaft, linkage connecting said armto one of said bars, a, link fixed to said shaft and havingapproximately the length of said arm, means for oscillating said links,a pusher on said arm and adapted to extend close to said arcuatesection, and a connection from said shaft to the other bar.

8. In a conveying apparatus, two spaced receptacles, straight railsections over said receptacles, an arcuate section connecting saidstraight rail sections, pusher bars slidably mounted along said straightsections, pushers extending from said bars toward said straightsections, a shaft rotatably mounted in the center of curvature of saidcurved section, a pair of arms fixed to said shaft, linkage connectingsaid arms respectively to said bars, a link fixed to said shaft, meansfor oscillating said link, said arms being spaced apart half the angularextent of said arcuate section and having each approximately the lengthof said link, and pushers on said arms and adapted to extend close tosaid arcuate section.

9. A conveying apparatus, two spaced rows of receptacles, an alinedseries of spaced rail sections fixedly mounted over each row, an arcuatesection joining the end sections of said series, a chassis movablymounted over said receptacles, means for moving said chassis up and downover said receptacles, a series of spaced rail sections carried by saidchassis and adapted to fit in the spaces between the first namedsections in the lower position of the chassis, slidably mounted pusherbars carried by said chassis, pushers carried by said bars in closeproximity to the movable rail sections and adapted to engage work on theseveral rail sections in either position of the chassis, a shaftrotatably mounted in the center of curvature of said curved section, anarm fixed to said shaft, linkage connecting said arm to one of saidbars, means for oscillating said shaft, a pusher on said arm and adaptedto extend close to said arcuate section, and a connection from saidshaft to the other bar.

10. A conveying apparatus, two spaced rows of receptacles, an alinedseries of spaced rail sections fixedly mounted over each row, an arcuatesection joining the end sections of said series, a chassis movablymounted over said receptacles, means for moving said chassis up and downover said receptacles, a series of spaced rail sections carried by saidchassis and adapted to fit in the spaces between the first namedsections in the lower position of the chassis, slidably mounted pusherbars carried by said chassis, pushers carried by said bars in closeproximity to the movable rail sections and adapted to engage work on theseveral rail sections in either position of the chassis, a shaftrotatably mounted in the center of curvature of said curved section, apair of arms fixed to said shaft and spaced apart half the angularextent of said arcuate section, linkage connecting said armsrespectively to said bars, means for oscillating said shaft, and pusherson said arms and adapted to extend close to said arcuate section.

11. A conveying apparatus, two spaced rows of receptacles, an alinedseries of spaced rail sections fixedly mounted over each row, an arcuatesection joining the end sections of said series, a chassis movablymounted over said receptacles, means for moving said chassis up and downover said receptacles, a series of spaced rail sections carried by saidchassis and adapted to fit in the spaces between the first namedsections in the lower position of the chassis, slidably mounted pusherbars carried by said chassis, pushers carried by said bars in closeproximity to the movable rail sections, and adapted to engage work onthe several rail sections in either position of the chassis, a shaftrotatably mounted in the center of curvature of said curved section, anarm fixed to said shaft, linkage connecting said arm to one of saidbars, a link fixed to said shaft and having approximately the length ofsaid arm, means for oscillating said links, a pusher on said arm andadapted to extend close to said arcuate section, and a connection fromsaid shaft to the other bar.

12. A conveying apparatus, two spaced rows of receptacles, an alinedseries of spaced rail sections fixedly mounted over each row, an arcuatesection joining the end sections of said series, a chassis movablymounted over said receptacles, means for moving said chassis up and downover said receptacles, a series of spaced rail sections carried by saidchassis and adapted to fit in the spaces between the first namedsections in the lower position of the chassis, slidably mounted pusherbars carried by said chassis, pushers carried by said bars in closeproximity to the movable rail sections and adapted to engage work on theseveral rail sections in either position of the chassis, a shaftrotatably mounted in the center of curvature of said curved section, apair of arms fixed to said shaft, linkage connecting said armsrespectively to said bars, a link fixed to said shaft, means foroscillating said link, said arms being spaced apart half the angularextent of said arcuate section and having each approximately the lengthof said link, and pushers on said arms and adapted to extend close tosaid arcuate section.

13. In a conveying apparatus, a series of receptacles, an alined seriesof spaced rail sections fixedly supported over said receptacles, achassis movably mounted over said receptacles, means for moving saidchassis up and down over said receptacles, a series of spaced railsections car ried by said chassis and adapted to fit in. the spacesbetween the first named sections in the lower position of the chassis,slidably mounted pusher bars carried by said chassis, pushers carried bysaid bars in close proximity to the mow able rail sections and adaptedto engage work on the several rail sections in either position of thechassis, and means for reciprocating said bars in both positions of thechassis, said pushers being spaced unequally at various parts of saidrail sections.

14. In a conveying apparatus, a series of receptacles, an alined seriesof spaced rail sections fixedly supported over said receptacles, achassis movably mounted over said receptacles, means for moving saidchassis up and down over said receptacles, a series of spaced railsections carried by said chassis and adapted to fit in the spacesbetween the first named sections in the lower position of the chassis,slidably mounted pusher bars carried by said chassis, pushers carried bysaid bars in close proximity to the movable rail sections and adapted toengage work on the several rail sections in either position of thechassis, and means for reciprocating said bars in both positions of thechassis, said pushers being spaced unequally at various parts of saidrail sections, said pushers being adjustable length-- wise on said bars.

15. In a conveying apparatus, a plurality of aligned work treatingtanks, a fixed work rail extending over and along said tanks, a slidablymounted pusher bar extending along and movable along said rail, aplurality of pushers spaced along a length of said bar at one of saidtanks, another plurality of pushers spaced along an other length of saidbar at another of said tanks at a spacing unequal t0 the spacing of thefirst named pushers, all of said pushers extending toward said rail toengage work thereon, and means for reciprocating said bar in equalstrokes slight- 1y greater than the spacing of either of the pluralitiesof pushers.

16. In a conveying apparatus, as set forth in claim 15, the pushers ofthe first plurality being spaced equally among themselves, and thepushers of the second plurality being spaced equally among themselves.

JOHN V. DAVIS.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,446,594 Stadler Feb. 27, 1923 1,467,409 Wilkinson Sept. 11,1923 1,736,935 Navarre Nov. 26, 1929 2,112,164 Kronsbein Mar. 22, 19382,143,116 Todd Jan. 10, 1939 2,245,673 Huenerfauth June 17, 19412,479,322 Davis Aug. 16, 1949

